1. Field of the Invention
The present invention relates to an apparatus that will remove thorn members from the surface of cactus leaves and, in particular, concerns two separate hand-held implements used in combination to secure and dethorn the cactus leaf.
2. Description of the Related Art
The nopal cactus leaf is well known in Mexico and the southwestern United States as a food staple and, in some circles, a delicacy. The fleshy leaves of the nopal cactus are large, circular, paddle-like members that can grow to be 7 inches in length, 4 inches in width and 0.5 inches thick. Generously distributed across the surface area of the cactus petal are a plurality of sharp thorny protrusions that may extend well over 1 inch in length. The razor sharp, prickly tips of the thorns create a protective barrier against animals that would otherwise feed on the fleshy nopal petal.
The nopal petal provides a healthy food source rich in vitamins A and C and is served up in a wide range of food dishes. The petal is commonly boiled in water, drained then diced into small wedges and mixed with onions, potatoes, and eggs. There are numerous other ways of serving this dish.
To prepare the nopal petal for consumption requires first removing the thorns that grow in clusters or clumps from small mounds along the surface area and edges of the cactus leaf. To peel away the thorns from the petal typically requires the use of both hands. One hand is used to secure and position the cactus petal while the other hand manipulates a knife blade to preferably slice along at the bottom of the thorn mound. The user grasps the knife handle in his or her hand and moves the knife with the blade slicing into the thorn mound such that the blade is generally travelling in a forward motion parallel to the plane of the cactus petal. It is common for the cactus petal to have a non-uniform flat surface with raised edges. Hence, slicing thorn mounds in this fashion with a straight blade knife may result in the knife tip gouging and tearing the edible portion of the raised edge of the nopal cactus tissue. Hence, using a knife often results in waste of the edible cactus tissue.
Moreover, to achieve the most effective slicing position of the knife blade against the thorn mound resulting in the least amount of petal waste, the knife hand is positioned directly over and against the petal surface. In particular, the slicing motion maintains the blade edge initially at the base of the thorn mound and continues with the blade cutting at a plane generally parallel to the petal surface through the mound. This approach is problematic because sections of the hand, including the thumb edge, the knuckles and the palm, scrape along the thorny cactus surface, resulting in cuts and abrasions. As a consequence, people often end up using the tip of the knife blade to remove the thorns which is less effective.
Furthermore, since the knife blade is straight, the cactus petal must be continually handled by the user so that the petal can be rotated and maneuvered to achieve the optimal positioning of the knife blade on the thorn mound base. The handling of the cactus petal results in injuries to the person and also makes the dethorning of the cactus less efficient.
To address this need, various cactus dethorning devices have been developed. In particular, U.S. Pat. No. 5,062,210 to Arroyo discloses an inverted V-shaped apparatus with a conventional razor blade adapted to fit within the open end of the V-shaped support handle. The elongated thin cylindrical side support members forming the V-shaped support handle extend approximately 6 inches outward and at an angle from each end of the wafer thin razor blade, to connect non-rigidly at the apex of the V. The attached blade is secured in a manner that is generally perpendicular to the side support members such that the blade edges are positioned to be used in the same plane as the cactus petal surface. To manipulate the apparatus, the user must grasp the angled side supports in the palm of the hand and scrape or peel away the thorns by positioning one edge of the blade adjacent to the thorn mound, applying a generally circular or swirling slicing motion of the blade into the thorn mound and then pulling upward and away from the cactus petal.
The non-rigid connection at the apex of the V-shaped blade handle allows the side members to be flexibly squeezed inward to cause the razor blade to bow outward in a concave manner. The concave blade edge can be preferably fixed to a desired shape by manipulating a transverse tie member to lock the handle support members at a specific distance apart from each other. A concavity to the cutting blade produces a better approach toward slicing away at the thorn mound by having the two extreme ends of the blade angled away so as not to gouge or scar the surrounding petal surface.
While the 6 inch, V-shaped handle disclosed in the Arroyo patent allows for the user to peel away the thorn mounds without putting the hand at risk of cuts and abrasions, the thin blade may fracture or detach from the flimsy support members due to the resistance provided by the thorn clumps. In addition, the blade side supports being perpendicular to the blade provide the user with an awkward and uncomfortable angle with which to slice and peel away the nopal thorn mounds, resulting in a generally awkward method of dethorning.
In particular, it is difficult to use the Arroyo device because the side members supporting the blade do not provide a substantial, comfortable surface area for the fingers and thumb to curl around and grasp. The hand, being distanced from and positioned directly over the cutting blade, makes blade manipulation more difficult because the user is unable to apply the necessary force and torque to the surface of the blade edge with the same degree of control that could otherwise be delivered by a typical knife. Slicing into the base of the thorn mound with the Arroyo device dictates the hand move pivotably about the wrist joint in up and down motions forming various angles between the forearm and the hand. A possible alternative to this motion would be to keep the wrist joint stiff and manipulate the cutting tool with the hand and forearm acting as one solid member. Either movement requires positioning the hand directly over the blade which does not capitalize on the otherwise stronger force and torque a cutting edge could deliver when the blade edge and hand act as a single member in generally the same relative plane of motion. In addition, this hand position relative to the cutting blade results in petal dethorning in a less precise manner due to the limited force and control applied to the cutting blade.
Another cactus dethorning apparatus is disclosed in U.S. Pat. No. 5,196,036 to Lamas. Lamas illustrates a hand-held inverted U-shaped device with the attachment of a razor blade member positioned between the open ends of the U-shaped handle. As with the Arroyo device, the blade is attached perpendicular to the side supports of the handle and used generally flush against the surface of the cactus petal. The same awkward and unnatural hand motions apply to the Lamas dethorning tool that were cited in reference to the Arroyo disclosure.
Further, both the Arroyo and the Lamas disclosures do not solve the more general problem associated with dethorning a nopal cactus petal which is the lack of a suitable method for securing the cactus petal in a rigid position against a flat surface allowing the removal of the thorn clusters. In particular, it is necessary to manipulate and secure the thorny cactus petal with one hand while using the other hand to slice and dethorn the petal surfaces and edges, resulting in painful cuts, abrasions and embedded thorns to the thumb, finger tips and palm area of the securing hand.
From the foregoing, it will be appreciated that there is a continuing need for a device for removing thorns from the nopal cactus petal, that is as natural and comfortable to use as a knife, and provides a design that maintains the user""s fingers at a safe distance from the nopal""s sharp thorns. In addition a tool is needed where the cutting blade and handle is a structurally solid member and the blade is not prone to detachment or breakage.
Furthermore, there is also a need for an improved manner of securing the cactus petal in position against a flat surface so that dethorning can be performed on the nopal petal without exposing the securing hand to cuts and abrasions and which will prevent the cactus petal from shifting around on the worktable to allow more precise and efficient dethorning with less waste or mutilation of edible cactus tissue.
The aforementioned needs are satisfied by the dethorning tool set of the present invention. In one aspect, the dethorning tool set includes a cutting knife that has a handle and a curved blade extending out of a first end of the handle. The curved blade has at least one cutting edge defined along at least one of the edges of the blade. Since the blade extends outward from a first end of the handle, the blade can be moved in a direction parallel to the plane of the petal with the user""s hand located generally above and to the side of the petal. As the user""s cutting hand is moving side to side, the user can exert greater downward force on the thorn mounds via the knife blade to remove the thorn mounds. The downward force also flattens out the uneven nopal areas for easier and faster thorn removal.
The curved blade, in one aspect is curved so that the concavity of the blade is located above the cutting edge when the user is holding the cutting knife. In one aspect, the handle is located above a line extending from the upper edges of the concavity such that the user""s hand is located above the plane of the cactus while the user is manipulating the cutting knife to dethorn the cactus. In this way, the user""s cutting hand is removed from the plane of the cactus thereby reducing the likelihood that the user""s hand will be injured during the dethorning process.
In another aspect, since the cutting blade is curved, a cutting location along the at least one cutting edge of the knife can be defined by the user manipulating the handle in a direction that is generally perpendicular to the plane of the handle. Hence, the user can cut thorn mounds located at different positions across the petal with less movement and less handling of the petal. This improves the efficiency of removing the thorns and also reduces the handling of the petal which reduces the risk of injury to the user.
In another aspect of the invention, each of the edges of the blade are cutting edges which permits the knife to be used to cut thorns off of the cactus in both a forward and backwards direction. Moreover, in one embodiment, the distal end of the knife blade is rounded and not pointed which reduces the likelihood of the knife end inadvertently gouging the cactus petal during removal of thorn mounds. The distal end of the knife blade can also define a cutting surface that can be used to trim the outer perimeter of the cactus petal or gouge out hard to remove thorns.
In another aspect of the invention, the tool set includes a securing knife having a handle with a blade extending outward therefrom. The blade defines a cutting surface that is normal to the direction of the handle such that the blade can be inserted into a portion of the petal thereby permitting the user to secure the petal against a surface with the securing knife during manipulation of the cutting blade. Hence, the user can secure or rotate the petal without using his or her hands thereby reducing the risk of injury from the thorns of the cactus.
The tool set of the present invention thereby allows for removal of thorns from cactus petals in a more efficient manner. Moreover, the cutting knife and the securing knife are both configured so as to reduce the risk of injury to the user as a result of inadvertent contact with the thorns of the cactus. These and other objects and advantages will become more fully apparent from the following description taken in conjunction with the accompanying drawings.